It has previously been proposed to make halogen incandescent lamps by fitting special metal elements into plastic sockets which, then, can be assembled in various fixtures, in lamp reflectors, and the like. The manufacture of the separate metal holders, plastic holders and the like are costly and cause assembly and manufacturing difficulties. This is particularly so for halogen incandescent lamps of e.g. 6 or 12 V and low power, e.g. a few watts, such as 5 watts or less, although the power consumption itself is not a limiting factor.